Apparatus for applying coating



Juny 31, 1923, 4 1,463,332

L. H. PARKER ET AL y APPARATUS FOR APPLYING COATING Original Filed Oct. 9. 1920 LEE H. PARKER, '0F BOSTON. AND HERBERT W. vDAY, OF WOLLASTON, MASSA- CHUSETTS, ASSLG'NORS TO SPRAY ENGINEERING COMPANY, OF BOSTON, MS- SAGEUSETTS, A CORPORATION OF MASSACHUSETTS.

.A PIARATUS FOR .A PPLYING COATING.

- Original application led October 9, 1920, Serial No. 415,737. Divided and this application led March 1, 1922. serial no. 540,116.

the accompanying drawings, is a specifica-` tion, like characters on the drawings representing. like parts.'

This application is a division of our co` pending application Serial No. 415,737, filed October 9, 1920, now Patent No. 1,425,333.

This invention relates to apparatus for applying coating and which while it may be of general application and applicable to coating applying devices, apparatus and methods of various types, is in the disclosed embodiment an improvement upon the invention disclosed in the patent to Herbert lV. Day, No. 1,321,014, dated November 4, 1919.

The coating, if a liquid, maybe a paint,

. japan, varnish or other suitable coating medium, or it may if desired be a solid in powdered form, and the material or surface to which itis to be applied may be of any character such for example as Wood,` metal or other material.

An important object of our invention is to provide an industrial tool or appliance and to perfect a method whereby paint or other coating material may be projected onto a surface, and even at some considerable distance from the user of the tool or appliance, without any scattering of the coating material beyond those parts of the surface that are intended to be coated. Other ob Fig. 3 is a view, partly in side elevation and partly in vertical section, Q the dis..

charge end of a coating tool and showing a further embodiment of the invention.

We shall proceed to describe our invention as applied to a paint gun or coating appliance like that shown in the said patent to Day, but it is distinctly to be understood that our invention is in no wise limited in its application to such type of gun or appliance, -but that it may be'employed upon yguns or appliances of various other types. of one type of gun or appliance to whichl the invention is applied is in no'sense a limi tation upon the scope of our invention.

The tool or appliance may be of any suitable material7 but is preferably metallic and may be of the general form shown in the patent to Day, No. 1,172,233, dated February 15, 1916, or of any other suitable form or construction. The body 1 is preferably The ensuing description therefore provided with a handle or extension 2 lintegral therewith and provided with a guard 3 enclosing the free end of the valve operating lever 4 pivoted at 5 upon the body 1. The said operating lever 4 is represented as of general trigger form.

The handle 2 is provided with a passage 6 for the paint or other suitable coating liquid or powder which may be supplied through gravity or under pressure if desired and also with a passage 7 for the air or other suitable fiuid under pressure. In the form of tool herein shown we have represented the passages 6,'7, as pipes suitably secured in the body 1 and as communicating at their inner ends with passages 8, 9 cored or -otherwise suitably provided in the body 1. Controlling the paint supply'rpassage 8 is a valve which may be of any suitable form, but which is herein represented as an axially movable piston or plunger 10 positioned Within a valve casing 11 and having a stem 12 extendin casing into contact wit here shown as a piston or plunger is northrough the valvsthe operating" le- -ver 4, as clearly-shown in Fig. 1. The valve mally held seated by a coiled spring 13 surrounding the stem 12 and seated in a recess 14 in a cap 15 threaded at 16 into the body 1 which is similarly threaded at 17.l

The passage '9 for the air is controlled b i a Similar when@ herein ShQWIl, 'D11t Pr@ erably the same as the corresponding valve 18 shown in Fig. 2 of the patent to Herbert W. Day, No. 1,368,612, dated February-15, 1921, the spindle of such valve contacting with the valve operating lever preferably so shaped as to engage both valves. y u

'llhe body 1 is cored to provide a longi tudinal passage 20 which is internally threaded at 21, 22 for the reception respectively of a tubular member 23 threaded at 24 and a needle valve 25 Ythreaded at 26. The tubular member 23 at its forward end is preferably suitably formed to permit the passage of the coating material issuing from the valve chamber into the passage 27 and thence into the circumferential space 28. For this purpose the forward end of the tubular member is preferably square at 29. 'lhus the coating material when the valve 10 is opened is permitted to flow through the passage 6, the valve casing 11, the passages 27, 28, and thence past the square formation 29. Upon the forward end of the tubular member is threaded or otherwise positioned a cap 30, which may if desired be similar to the correspondingfmember in the said Day Patent No., 1,172,233. The needle valve 1s seated at the outer end in the cap 30 as indicated in Fig. 1, and the forward end of the said needle valve is guided andY positioned by any suitable means', as for example by `a coiled wire 31 encirclingr the head of'the valve and maintaining it in a central position when the valve is unseated:

rfhe rear end of the valve 25 may be provided witha suitable lock nut 32.

The air passage 9 is in communication with a passage 33 indicated in dotted lines in Fig. 1, and which is itself in communication with the valve chamber containing the valve 18. Extending from such valve chamber is 'au airl passage 34 indicated in dotted lines in Fig. v1 and communicating with a passage 35 forming an enlargement of a passage 36 of the tubular member 20. When the valve casing is opened, the air v Hows through the passage 33, pastthe valve 19, through the passages 34, 35, and into the passage 36 governed or controlled` by the needle valve 25.

Upon the' outer end of the body 1 is threaded or otherwise suitably secured a preferably 'cap-like member 37 herein shown as having a concaved orcurved .ir-I ner surface 38 and a small central opening 39 in line with thelaxis of the needle valve l25. 'llhe length of the threaded portion 40 of the cap like member 37 is sufiicient to permit adjustment of the member 37., so as to provide for the effective formation. of a lm and the `variation of the thickness `thereof as .described in the said Day Fatent No. 1,172,233. Such film is constantly l formed'V and maintainedby'capillary lacneeaeea tion between the surface 38 and the outersurface 41 of the inner cap 30, which are brought close enough together to insure such action. The air entering through the passage 36 breaks through the film at the central part of the cap and discharges the same upon the worlr in very fine globules. Said lilm is constantly broken by the air or other fluid, but is constantly restored through theraction of capillarity. the coating material may be merely under suction due to capillary action. The mairf tenance of the supply of coating material is not dependent upon the presence of the air pressure which is used merely to break the film and discharge the globules. Five effect through the described construction very fine division of the coating material as set forth in theL7 said Day FatentNo. 1,172,233.

lil/while we have described at some length means whereby a film of coating material is formed, disrupted and discharged, we desire it to be understood that our'invention is not limited in its application to th formation of a film, since the coating terial may be brought or supplied to the point of ultimate discharge in any suitable manner, whether as a film formation or otherwise, or as shown for example in the patent to Burdick, No. 649,430, dated Mar 15, 1900, and in the patent to De Vilbis:C and .Muellen No. 1,260,522, dated March 2e, 1918.

'llhe construction of parts thus .far described eff'ects the formation of a mass of spray of general conical form issuing through the orifice 39, but generally circular in cross-section. This result is effected by the disrupting of the film formed between the cap-like vmembers 30, 37, through the agency of the air or other suit--k able fluid in the manner already described.

Hence .'51s disclosed in the said lDay Patent, No

vided for discharging supplemental jets of air upon the discharged spray for the purpose of changing the vshape of!v the discharged spray from .circular form into that of a relatively thin sheet, the disclosure in the said Day Patent No. 1,321,014 being of, means whereby the mass of spray as discharged is given any form between that of a relatively thin sheet and a cone or mass circular in cross section.

Uur invention constitutes an advance and an improvement upon those tools `or appliances having means for discharging sup` plemental jetsaof air upon the discharged ,coatingmateriah and as previously stated is not limited in its application to those types of tools or appliances wherein a film formation is created or established. We will, however, disclose the essential features of our .invention as applied to a tool mental air jets und or appliance wherein such film formation 1s created. Y

In the use of the tool of our invention we are enabled to break up the coating ma-l terial into globules or particles of any desired fineness. The paint or othercoating material is broken up by the air issuing past the needle valve 25 to a certain degree of fineness, but it is frequently desirable to break up the coating material to greater degrees of fineness. B providing -supple- U er iilll force or pressure, the coating material is broken into particles or globules of the most extreme fineness. By modulating or varying the pressure of the supplemental air jets any desired intermediate degree of ineness of the coating par ticles is secured.

In the disclosed embodiment of the invention we provide a generally cylindrical conical member 42 having anyl suitable number, and herein two, tubular extensions or passages 43, 44, preferably diametrically opposed to each other and having discharge passages 45, 46, which as shown most clearly in Fig. 2, are-of substantial length transversely of said tubular passages 43, 44, and are desirably inclined toward each other as clearly represented in Fig. 1. Said discharge passages are formed as slots which may slope at any desired angle so thatthe supplemental sheets of discharged air may meet as at the point A in Fig l, or at a. point considerably in advance thereof. In either case, the supplemental air sheets act upon the coat-ing material and air which are discharged through the passage 39 so as further to break up the same and also to provide a protective sheathing, wall or the like.

In addition we provide for the discharge of other supplemental air jets through small passages desirably circular in contour. Such passages, openings or perforations, may be at any desired points as for example at the points 45a, 46a in Fig. 1. This permits the dischar e of supplies of supplemental air u on te coating material already disc arged through the passage 39 and thereby effects a further breaking up of the material. The air discharged through the slots 45, 46a effects still further comminution of the discharged material and the air discharged through the openings 45, 46 provides for t e protective sheathing, coating or wall.

In certain forms of our invention the perforations 45a, 46".,for the supplemental air jets ma ment o the central or some other part of the slots 45, 46.

The two supplemental air passages 43, 44,

with their terminal openings 45, 46, 45, 46a, are respectively in constant communication t their inner ends through passages 47, 48

with an annular passage or lgroove 49 shown as formed in the outer surfacev of theforbe formed in or as an enlarge- Ward end of the body 1 and communicating through the longitudinally extending passage 49 with a passage 50 in the body memberl and which is in communication with' the main air passage 35 through a\70 small port 5l.

This port is controlled by a valve 52 threaded into an opening 53 of the body 1 and having a preferably .knurled head 54 by which it may be turned manually. The inner tapered head 55 of 'said valve is adapted to be seated so as to close the' port 51 or to be opened fully or to any desired extent, th'us regulating the air supply through the said passage 50. The valve 52 constitutes a reducing valve whereby the supplemental air pressure can be regulated if desired and whereby any desired degree of neness of the discharged coating ma-J terialmay be obtained. Obviously the annular groove 49 may be formed in the inner surface of the member 42.

In orderk effectively to seat and control the position of the cylindrical member'42, the body 1 is herein 'shown as provided with a spherical surface .56 uponwhich is received the correspondingly shaped inner surface57 of the cylindrical member 42. Cooperating with the said sphercal seat -is the guiding surface 58 of the-*cap-like member 37. i

With said guiding surface 58 there co-ntact thev projections 59, 60, which extend from the ll fth l ntal ir u l` aswa so esuppeme a s ppypbe 100 sages 43, 44. This construction. may varied as desired.

Cooperating to hold 'the cylindrical member 42 in position, there is desirably provided a coiled spring 61 between the inner end of the cap-like member 37 and the ycy'lindrical member 42.

While in the disclosed embodiment of the invention the supplemental air passages 47,

48 are represented as in constant communication with the annular groove or passage 49, whatever be the circumferential position of the cylindrical member 42, our 1nvention obviously is notl limited tosuch feature ofconstant communication, although this is desirable. In other types of tools or a pliances to which our invention may be ied, the supplemental air passage or passages may not be in constant communication with the source of compressed air su l oiivever, in the disclosed type or embodiment of our invention the discharge ofthe supplemental air jdts is not interrupted or cut ,olf by Lmovement of the cylindrical member 42, but t rough the manipulatlon of the` valveI 52.

Our invention, however, is not` vlimited inthis respect.

clined toward the axis oi;J the tool or appliance, or rather toward an outward prolongation of the said axis. ln such other types of coating tools as we are familiar with, the supplemental air jets are discharged at an inward inclination so as to intersect, it but very little extended, a prolongation of the anis ot the tool. The general result oiQ such construction is to transform the discharged coating material from a mass circular in cross-section into the form ot a rel atively thin sheet, though as already stated, in case of said Day patent 1,821,0111 any :term between that oi circle and a relatively thin sheet may be secured.

ln all said cases, however, the supplemental air jets are discharged directly onto the discharged coating material at a point close to the point of ultimate discharge of the coating material from the tool. ln none or said cases has any attempt been made to create by the supplemental air jets protective sheathings or air walls that substantially encompass or partially surround the discharged coating material which has been reduced to a sheet-like condition.

l'naccordance with the scope and purpose ot our invention we provide for la discharge of the supplemental air jet or jets in such a way and with such a result that the said j ets themselves become or are more or less iiattened out or transformed into layers of air, and which position themselves at the opposite laces ofthe discharged coating material. 'llhus the supplemental air jets perform several important results. rllhey serve first to flatten the discharge or spray of coating material into a general sheet-like form and since they themselves are more or less flattened in accordance with our invention, they-secondly constitute a protecting sheathing or envelope or an air wall or walls which ed'ectively prevent the outlying or smaller particles of the coating material from disseminating or tlying onto any part of the surface that is not desired to be coated. 0n the contrary, all the outlying particles are guided and directed in such a way that all the discharged coating material is received upon the surface in a relatively thin line. 'llhe result'isthat the user of the tool or appliance-may stand ata considerable distance from a wall or other surface that is to be coated and may project the coating material in the described relatively thin line upon the exact parts of thesurface desired without overlapping onto adjacent parts ot the surtace or onto other Surfaces.

rlFhe means ot our invention may be embodied in various types or forms of tools.

Preferably, however, we carry out our invention in substantially the following manincassa the desired result. The invention herein die closed therefore differs specilically trom that disclosed in our (zo-pending application Serial No. A115,737, wherein we have described certain prolongations, abutments, or mechanical parts i'or securing the desired resuitn j Within the scope of our yinvention prolongations or abutments may be positioned at any suitable point and may receive the impact ot the supplemental air jets in any suitable manner. ln llig. 3 we have represented 'the abutments, other forms of which are shown in our said co-pending application Serial No. 41m-15,737, as located with in the points ci discharge et the supplemental air jets. ln said Fig. 3, we have represented the supplemental air passages 62, 63 as prolonged as indicated at 6d, 65, though within the scope of our invention they may be oi' any desired length. sirably the prolongations 6d, 65 are made as .separate nipples threaded internally as indicated at 66, 67, and received upon enter-- nally threaded parts 68, 69 ot the passages 62, 63. At their forward extremities the said nipples 6d, 65 are provided with discharge passages 70, 71, which may be termed as lsmall perforations or otherwise, and between said discharge passages and the point 7@ Q of the discharge ot coating material, we provide abutments 73, 711, which desirably are rounded substantially as shown. The said abutments 73, 7d are so located and are so shaped as to be stream lined, whereby the supplemental air discharge from the openings 70., 71 tends to follow the contour of said abutments, and thus being .directly inwardly toward eabh other will strike the discharged coating material, reducing the same to more or less ot a line, and at the same time `will form themselves into a protecting wall or tubing tor the coating material produced. ln the use of a paint gun suchas herein disclosed, there is created somewhat ot a vacuum adjacent to the point et disilo charge of the coating material, and the result et this isto cause the supplemental air jet to hug or keep in contact so long as possible with the abutment 7 3, 7d.

Having thus described one illustrative embodiment omyinventiom li desire it to be understood that 4although specific terms are employed they are used in a` generic and descriptive'sense and not tor purposes ot limitation, the scope ot the in` vention being set forth in the following claims.

Claims:

1. Means for applying coating comprising means to supply coating material, means to subject the same to the .action ot compressed air, thereby edecting the V4disn'zlnrge of the coati material, means to discharge com-v presse air supplementally upon-I the discharged air so that the latter is itself reduced to sheet form Haring from its points of discharge.

2. Means for applying coating comprising means to supplyv coating material, means to subject the same to the action of compressed air, Vthereby effecting the discharge of the coating material, means to' discharge compressed air supplementally upon the discharged coating material at opposite sides,

of the discharge of coating material, thereby reducing said discharge of coating material to sheet form :flarinv from the point of discharge therefrom an unconfined at its edges, and means to discharge other supplemental jet-s onto the said supplementally discharged air so that the latter is itself reduced to sheet form.

3. Means for applying coating comprising means to supply coating material, means to subject the same to the action of compressed air, thereby effecting the discharge of the coating material, means to discharge compressed air supplementally upon the discharged coatingl material at opposite sides of thel discharge of coating material, thereby reducing said discharge of coating material to sheet form flaring from the point of discharge therefrom and unconned at its edges, and means to discharge other supplemental jets of air onto the said supplementally discharged air, so that the latter is itself reduced to sheet form Haring from its points of discharge and unconfined at the pressed air supplementally upon the discharged coating material at opposite sides of the discharge of coating material, thereby reducing said discharge of coating material to sheet form Haring from the point of discharge therefrom and unconfined at its edges, and means to discharge other supplemental jets onto the said supplementally discharged air in general superposition upon the said supplementally discharged air.

5. Means for applying coating comprising means to supply coating material, means to subject the same to .the action of compressed air or othermotive agent, thereby eii'ecting the discharge of the coating material and means to discharge compressed air or other motive agent at opposite sides of the discharge of coated material and in a plurality of jets at each of said opposite sides.

6. Means for applying coatingl comprising means to supply coating material, means to subject the same to the action of compressed air or other motive agent, thereby effectingl the discharge of the "coating material and means to. discharge compressed air or other motive agent at opposite sides of the discharge of coated material and in a plurality 'of jets at each of said oppositesides and in general superposition-at eachof said opposite sides.

7. Means for applying coating comprising means to supply coating material, means to subject the same to the action of a motive agent, thereby effecting the discharge of the coatin material in a mass generally circular 1n cross section, means to discharge a motive age-nt supplementally upon the discharged mass, thereby to reduce it to'sheet form, and means at opposite sides of the point of discharge of the coating material but between the same and the points of discharge of the motive agent supplementally,

to cause such supplementally discharged motive agent to assume the form and position of a sheet like protective cocer for the .dis-

charged mass of coating material..

In testimony whereof, we have slgned our names to this specification.

LEE H. PARKER. HERBERT WLDAVY. 

